The Antioxidant Capacity of Extracts from Taiwan Indigenous Purple-leaved Vegetables

臺灣鄉土紫葉蔬菜萃取物的抗氧化能力

湯淑貞(Shu-Chen Tang) ； 羅筱鳳(Hsiao-Feng Lo) ； 林冠宏(Kuan-Hung Lin) ； 張粲如(Tsan-Ju Chang) ； 楊棋明(Chi-Ming Yang) ； 趙璧玉(Pi-Yu Chao)

《臺灣園藝》 59卷1期 (2013/03) Pp. 43-57

摘要

The aim of this study was to evaluate the antioxidant components and activity of Taiwan indigenous purple-leaved vegetables, including gynura (Gynura bicolor DC.), sweet potato [Ipomoea batatas (L.) Lamark], celosia (Celosia argentea L.), edible amaranth (Amaranthus tricolor L.), perilla (purple-leaved and bicolored-leaved) [Perilla frutescents (L.) Britton], and heartleaf houttuynia (Houttuynia cordata Thumb.). The same vegetables with green leaves were used as controls. The items analyzed were the antioxidant components including polyphenol, flavonoids, anthocyanidins, and porphyrins. The antioxidant activity including reducing power, chelating Fe^(2+) ion, and scavenging of 1,1-disphenyl-2-picryl-hydrazyl (DPPH) radical and superoxide anion, the inhibition of conjugated diene formation, and malondialdehyde (MDA) formation, and lag phase of low density lipoprotein (LDL). The results showed that purple-leaved sweet potato was rich in polyphenol, flavonoids and porphyrins. Both purple- and bicolored-leaved perilla (lines 1 and 2) contained relative high levels of anthocyanidins and porphyrins. Purple-leaved perilla line 1 and green-leaved sweet potato had highest reducing power in aqueous extract. Aqueous extract of light green-leaved edible amaranth and methanolic extract of heartleaf houttuynia exhibited the highest scavenging superoxide capacity. The aqueous extracts of all vegetables showed very low DPPH scavenging activities. The inhibitions of MDA formation in LDL system of purple and green-leaved sweet potato were higher than other aqueous extracts. In methanolic extracts, welwet plant, Taiwan welwet plant, purple and green-leaved sweet potato, heartleaf houttuynia, and purple-, bicolored- and green-leaved perilla (lines 1, 2 and 3) had much higher activity to prolong the lag phase of LDL oxidation (P ＜ 0.05). In the above three tested antioxidant activity assays (the inhibition of conjugated diene formation, the inhibition of MDA formation, and the lag phase of LDL oxidation), purple-leaved sweet potato exhibited higher antioxidative capacity compared to other vegetables.

關鍵字

類黃酮 ； 還原力 ； 共軛雙烯 ； 丙二醛 ； 遲滯期

並列摘要

The aim of this study was to evaluate the antioxidant components and activity of Taiwan indigenous purple-leaved vegetables, including gynura (Gynura bicolor DC.), sweet potato [Ipomoea batatas (L.) Lamark], celosia (Celosia argentea L.), edible amaranth (Amaranthus tricolor L.), perilla (purple-leaved and bicolored-leaved) [Perilla frutescents (L.) Britton], and heartleaf houttuynia (Houttuynia cordata Thumb.). The same vegetables with green leaves were used as controls. The items analyzed were the antioxidant components including polyphenol, flavonoids, anthocyanidins, and porphyrins. The antioxidant activity including reducing power, chelating Fe^(2+) ion, and scavenging of 1,1-disphenyl-2-picryl-hydrazyl (DPPH) radical and superoxide anion, the inhibition of conjugated diene formation, and malondialdehyde (MDA) formation, and lag phase of low density lipoprotein (LDL). The results showed that purple-leaved sweet potato was rich in polyphenol, flavonoids and porphyrins. Both purple- and bicolored-leaved perilla (lines 1 and 2) contained relative high levels of anthocyanidins and porphyrins. Purple-leaved perilla line 1 and green-leaved sweet potato had highest reducing power in aqueous extract. Aqueous extract of light green-leaved edible amaranth and methanolic extract of heartleaf houttuynia exhibited the highest scavenging superoxide capacity. The aqueous extracts of all vegetables showed very low DPPH scavenging activities. The inhibitions of MDA formation in LDL system of purple and green-leaved sweet potato were higher than other aqueous extracts. In methanolic extracts, welwet plant, Taiwan welwet plant, purple and green-leaved sweet potato, heartleaf houttuynia, and purple-, bicolored- and green-leaved perilla (lines 1, 2 and 3) had much higher activity to prolong the lag phase of LDL oxidation (P ＜ 0.05). In the above three tested antioxidant activity assays (the inhibition of conjugated diene formation, the inhibition of MDA formation, and the lag phase of LDL oxidation), purple-leaved sweet potato exhibited higher antioxidative capacity compared to other vegetables.

並列關鍵字

flavonoids ； reducing power ； conjugated diene ； malondialdehyde (MDA) ； lag phase